1. Field of the Invention
The present invention relates in general to antennas. More particularly, the present invention relates to multi-band antennas.
2. Description of Related Art
Currently in the wireless communication industry there are a number of competing communication protocols that utilize different frequency bands. In a particular geographical region there may be more than one communication protocol in use for a given type of communication e.g., wireless telephones. Examples of communication protocols for wireless telephones include GSM 900, AMPS, GSM 1800, GSM 1900, and UMTS. In addition, certain communication protocols may be exclusive to certain regions. Additionally future communication protocols are expected to utilize different frequency bands. It may be desirable to provide xe2x80x98future proofxe2x80x99 communication devices that are capable of utilizing a currently used communication protocol, as well as communication protocols that are expected to be utilized in the near future.
It is also desirable to be able to produce wireless communication devices capable of operating according to more than one communication protocol. The latter may necessitate receiving and transmitting signals in different frequency bands. It is desirable to have smaller antennas for wireless communication devices that are capable of operating in multiple frequency bands, rather than having separate antennas for different bands.
Wireless communication devices have shrunk to the point that monopole antennas sized to operate at the operating frequency of the communication device are significant in determining the overall size of the communication devices in which they are used. In the interest of user convenience in carrying portable wireless communication devices, it is desirable to reduce the size of the antenna and it is desirable to have an antenna that can be fit within in a device housing in a space efficient manner.